Keying device for embedment anchor



NOV. 1966 T. H. JEFFERSON ETAL 3,282,002

KEYING DEVICE FOR EMBEDMENT ANCHOR Filed Dec. 19, 1963 F162 /2 Fig.3

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5/44. F. A nzqo v WW4 M 3,282,002 KEYING DEVICE FOR EMBEDMENT ANCHOR Taylor H. Jefferson and Billy F. Narron, Alexandria, Va., assignors to the United States of America as represented by the Secretary of the Army Filed Dec. 19, 1963, Ser. No. 331,980 7 Claims. (Cl. 52162) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to us of any royalty thereon.

The present invention relates to improvements in embedment anchors and more particularly to explosive driven light weight embedment anchors.

An object of this invention is to provide in an embedment anchor a keying device which, while not materially affecting the trajectory of the anchor, would nevertheless, upon the application of force from the anchor cable, the key being pushed into the earth above, would cause the anchor to rotate away from its position substantially parallel to the anchor cable, thereby providing a maximum resistance to withdrawal from the earth.

Other objects and advantages will be apparent to those skilled in the art in reference to the following description and the accompanying drawings in which:

FIG. 1 is a perspective view of one embodiment of our invention;

FIG. 2 is a plan view of a second embodiment of our invention;

FIG. 3 is a longitudinal edge view of the embodiment illustrated at FIG. 2 during the embodiment phase of operation;

FIG. 4 is a longitudinal edge view of the embodiment illustrated at FIG. 2 during the anchoring or withdrawal phase of operations;

FIG. 5 is a view of a third embodiment of our invention;

FIG. 6 is a partial plan view of still another embodiment of our invention; and

FIG. 7 and 8 illustrate plan and longitudinal edge views, respectively, of a further embodiment of our invention.

Briefly, our invention comprises the combination with an embedment anchor of a keying device comprising a fin, means for attaching the fin to the embedment anchor whereby the fin extends rearward of and substantially coplanar with the anchor as forward penetration into the earth is effected. Upon application of withdrawal force upon the anchor, when the fin is pushed into resisting earth, the attaching means allow the plane of the fin to form a reflex angle with the plane of the anchor. Thus, upon application of further withdrawal force, the fin or fins guide the anchor rotationally into a plane generally perpendicular to its plane of penetration.

Referring in detail to FIG. 1, embedment anchor 1 is provided with loop 5 to which is attached the bight of anchor cable 2. Fin 3 is hinge mounted as at 4 to embedment anchor 1. Stops similar to in FIG. 5 are provided on the body of the anchor to prevent the fin from rotating beyond the desired position, for effecting proper rotation of the anchor, the proper angle being determined by the density of the material into which the anchor is embedded.

FIGS. 2, 3 and 4, depicting a second embodiment of our invention, show fins 11 and 12, instead of being hinge mounted, being of a flexible or resilient material which is bent into the desired shape shown in FIG. 4, by the force of the material surrounding the anchor as pressure is applied to the anchor cable to seat the anchor.

FIG. 5 illustrates still another embodiment of this invention wherein inertial force from acceleration and drag hold the keying device 14 in a neutral position during the United States Patent 0 "ice.

embedment process. As an upward force is applied to the anchor cable, leaf spring 13 urges fin 14 to rotate into the keying position, key stop 15 preventing travel beyond the desired position.

FIG. 6 illustrates a more positive type keying action wherein strap 22 holds fin 20 in the neutral position during the embedment process. When the embedment process is completed, explosive bolt 23 releases strap 22 from fin 20, allowing leaf spring 24 to force fin 20 into the keying position. It will be appreciated that explosive bolt means 23 may be energized by any conventional means, for example via electrical cable 29 and a power source, not shown.

In FIGS. 7 and 8 fins 31 are each held in neutral position by a retainer strap 32 until completion of the embedment procedure. After embedment, the explosive bolts 33 upon energization via cable 39 free the fins 31 so that they may be pivoted at hinge 34 into the keyed position as shown in dotted outline in FIG. 8. This movement of the fins 31 through the connection of the keying bars 35 interconnecting the fins 31 with the rotating lug 37 moves this lug into the dotted position shown in FIGS. 8. Force exerted through a cable connected at 36 to lug 37 will rotate the anchor into the keying position.

Other variations may, of course, be resorted to without departing from the scope of this invention.

We claim:

1. An improved embedment anchor having tip and tail sections with a substantially planar surface configuration therebetween wherein substantially planar fin means are connected for movement to said tail section thereof,

said fin means adapted for planar alignment with said planar surface configuration and adapted to pivot in the vicinity of the connection to said tail section, and cable attachment means for applying a withdrawal force disposed on said anchor at a selected distance from said fin means connection thereto such that application of a withdrawal force subsequent to embedment of the anchor will effect a pivoting of said anchor with respect said planar fin means.

2. An improved embedment anchor as defined in claim 1 wherein control means are adapted to limit the degree of pivoting of said planar fin means with respect the planar surface of said embedment anchor.

3. An improved embedment anchor as defined in claim 2 wherein said planar fin means are adapted to pivot in response to anchor withdrawal forces applied substantially to the center section of said embedment anchor.

4. An improved embedment anchor as defined in claim 3 wherein said planar fin means are hinge coupled to said tail section thereof.

5. An improved embedment anchor as defined in claim 4 wherein said planar fin means incorporate leaf spring means adapted to apply a pivot force thereto and strap retaining means adapted to counter said pivot force, said strap retaining means including a breakable portion for releasing said pivot force.

6. An improved embedment anchor as defined in claim 5 wherein said breakable portion is an explosive bolt.

7. An embedment anchor body including a keying device comprising a fin hinge mounted upon said anchor body, said fin extending rearwardly of and substantially coplanar with said anchor body as forward penetration by the anchor is effected, a strap secured to said embedment anchor body and secured to said fin by explosive bolt means, means for energizing said explosive bolt means upon completion of forward penetration of said anchor body, connector bar means interconnecting said fin and a rotatable link located centrally of said anchor body, detonation of said explosive bolt forcing said fin to a positron to form a reflex angle with the plane of said anchor body, stop means carried by said anchor body to limit the reflex angle formed by said fin and means on said rotatable link for securing means for applying a force whereby upon application of such force substantially parallel to said anchor body rotation of the anchor body from an initial vertical position to a position substantially normal to the initial position is effected. 1

References Cited by the Examiner UNITED STATES PATENTS 1,273,890 7/1918 Loseth 52-162 Colvin 52-162 Brickman 52162 Aiken 52-162 Holmes 52155 X Smith 52-160 Anderson 1l4206 FRANK L. ABBOTT, Primary Examiner. 10 R. S. VERMUT, Assistant Examiner. 

1. AN IMPROVED EMBEDMENT ANCHOR HAVING TIP AND TAIL SECTIONS WITH A SUBSTANTIALLY PLANAR SURFACE CONFIGURATION THEREBETWEEN WHEREIN SUBSTANTIALLY PLANAR FIN MEANS ARE CONNECTED TO MOVEMENT TO SAID TAIL SECTION THEREOF, SAID FIN MEANS ADAPTED FOR PLANAR ALIGNMENT WITH SAID PLANER SURFACE CONFIGURATION AND ADAPTED TO PIVOT IN THE VICINITY OF THE CONNECTION OF SAID TAIL SECTION, AND CABLE ATTACHMENT MEANS FOR APPLYING A WITHDRAWAL FORCE DISPOSED ON SAID ANCHOR AT A SELECTED DISTANCE FROM SAID FIN MEANS CONNECTION THERETO SUCH THAT APPLICATION OF A 